The pulley system shown is at rest when the motor M starts pulling in rope so as to lift t...

The pulley system shown is at rest when the motor M starts pulling in rope so as to lift the 120 lb cargo C. For the first second of operation, the motor can produce a tension in the rope of the form F0(1 + t/τ), where F0 = 40 lb. Neglect the inertia of the pulleys and of the rope.

If τ = 0 5 s, use the impulse-momentum principle to determine the speed of the crate after 1 s.

Figure P5.17